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padervand--mohsen
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Removal of toxic heavy metal ions from waste water by functionalized magnetic core–zeolitic shell nanocomposites as adsorbents
, Article Environmental Science and Pollution Research ; Volume 20, Issue 6 , June , 2013 , pp. 3900-3909 ; 1614-7499 ; Gholami, M. R. (Mohammad Reza) ; Sharif University of Technology
2013
Abstract
Functionalized magnetic core–zeolitic shell nanocomposites were prepared via hydrothermal and precipitation methods. The products were characterized by vibrating sample magnetometer, X-ray powder diffraction, Fourier transform infrared spectroscopy, nitrogen adsorption–desorption isotherms, and transmission electron microscopy analysis. The growth of mordenite nanocrystals on the outer surface of silica-coated magnetic nanoparticles at the presence of organic templates was well approved. The removal performance and the selectivity of mixed metal ions (Pb2+ and Cd2+) in aqueous solution were investigated via the sorption process. The batch method was employed to study the sorption kinetic,...
Effective photocatalytic degradation of an azo dye over nanosized Ag/AgBr-modified TiO2 loaded on zeolite
, Article Journal Chemical Papers ; Volume 65, Issue 3 , June , 2011 , pp 280-288 ; 1336-9075 ; Tasviri, M. (Mahboubeh) ; Gholami, M. R. (Mohammad Reza) ; Sharif University Of Technology
2011
Abstract
Zeolite-based photocatalysts were prepared by the sol-gel and deposition methods. The photocatalysts were characterised by X-ray diffraction, nitrogen adsorption-desorption isotherms, FTIR spectroscopy, scanning electron microscopy and energy-dispersive X-ray spectrometry. The activity of the prepared photocatalysts was evaluated by the UV-induced degradation of acid blue 92, a textile dye in common use. The effect of various parameters, such as catalyst concentration, initial dye concentration, thiosulphate concentration and pH, on the rate and efficiency of the photocatalytic degradation of acid blue 92 was investigated. The results showed that each parameter influenced the degradation...
Synthesis and Investigation of Antibacterial Activity of Nanostructures Carbon Nitride g-C3N4 Photocatalyst under Visible Light
, M.Sc. Thesis Sharif University of Technology ; RoustaAzad, Reza (Supervisor) ; Vosoughi, Manouchehr (Supervisor) ; Padervand, Mohsen (Supervisor)
Abstract
Carbon nitride is a compound that has the proper energy gap (2.7 eV) for activities in the visible light. In this research, photocatalysts based on nanoporous Carbon nitride sheets was synthesized with three primary ingredient (urea, melamine and melamine hydrochloride) by pyrolysis method. Ag, Cu, Fe2O3 and Fe3O4 were added to the system to prevent the electron-hole recombination as well as increscent the photocatalytic activity. The chemical bonding state properties and microstructure of the synthesized photocatalysts were investigated by means of XRD, SEM, BET, FTIR, DRS and PL methods. In the first step of the research, the activity of prepared compounds was analyzed by visible light for...
Incredible antibacterial activity of noble metal functionalized magnetic core-zeolitic shell nanostructures
, Article Materials Science and Engineering C ; Volume 35, Issue 1 , Feb , 2014 , Pages 115-121 ; Janatrostami, S ; Karanji, A. K ; Gholami, M. R. (Mohamad Reza) ; Sharif University of Technology
2014
Abstract
Functionalized magnetic core-zeolitic shell nanostructures were prepared by hydrothermal and coprecipitation methods. The products were characterized by Vibrating Sample Magnetometer (VSM), X-ray powder diffraction (XRD), Fourier Transform Infrared (FTIR) spectra, nitrogen adsorption-desorption isotherms, and Transmission Electron Microscopy (TEM). The growth of mordenite nanoparticles on the surface of silica coated nickel ferrite nanoparticles in the presence of organic templates was also confirmed. Antibacterial activity of the prepared nanostructures was investigated by the inactivation of Escherichia coli as a gram negative bacterium. A new mechanism was proposed for inactivation of E....
Degradation of Model Textile Dyes in Wastewater using Visible-Light Active Photocatalysts
, M.Sc. Thesis Sharif University of Technology ; Soltanieh, Mohammad (Supervisor) ; Vossoughi, Manouchehr (Co-Supervisor) ; Padervand, Mohsen (Co-Supervisor)
Abstract
Textile dyes are a major category of organic pollutants and release of them in the environment causes serious problems. Among the most commonly used methods for colored wastewater, advanced oxidation processes, especially the photocatalytic process, are rapidly developing as a new and effective solution. However, there is still a need for high-level photocatalytic activity and improvement of this process to increase removal efficiency. In this study, we have tried to provide a higher performance for color removal using carbon nitride photocatalyst. Accordingly, two approaches have been proposed to improve the removal of rhodamine b, as one of the common dyes in the textile industries. The...
Systems designed with an ionic liquid and molecular solvents to investigate the kinetics of an SNAr reaction
, Article Progress in Reaction Kinetics and Mechanism ; Volume 38, Number 2 , 2013 , pp. 157-170 ; Padervand, M. (Mohsen) ; Gholami, M. R. (Mohammad Reza) ; Hallett, Jason P ; Sharif University of Technology
2013
Abstract
The microscopic features of binary solvent systems formed by molecular solvents (methanol, ethanol, 2-methylpropan-2-ol, water, pyridine, acetonitrile, 1-propanol, 2-propanol, dimethylformamide) and the ionic liquid ([bmim]BF4) as cosolvent were used to select mixed solvents with particular characteristics. Molecular-microscopic solvent parameters corresponding to these binary mixtures were utilised to study the kinetics of the nucleophilic substitution reaction between 2-chloro-3,5-dinitropyridine and aniline to investigate and compare the effects of the solvents on a model chemical reaction. For these mixtures, the solvation behaviour is dominated by both the dipolarity/ polarisability and...
Removal of an organic pollutant from waste water by photocatalytic behavior of AgX/TiO2 loaded on mordenite nanocrystals
, Article Research on Chemical Intermediates ; Volume 38, Issue 8 , 01 September , 2012 , pp 1975-1985 ; 1568-5675 ; Salari, H. (Hadi) ; Ahmadvand, S. (Seyed Saeid) ; Gholami, M. R. (Mohammad Reza) ; Sharif University of Technology
2012
Abstract
Mordenite (MOR) nanocrystals were synthesized using the hydrothermal method. Sol–gel and deposition methods were utilized to modify the zeolite surface with TiO2 and then AgBr or AgCl particles. Photocatalysts were characterized by using X-ray diffraction, Brunauer–Emmett–Teller (BET), and scanning electron microscopy techniques. Activity was evaluated by photodegradation of Acid Blue 92 as an azo dye. The effect of silver halide deposition on the photocatalytic behavior of the prepared nanocomposites was studied under both ultraviolet (UV) and visible light, and the results were compared. The results showed that AgCl/TiO2/MOR was more active under UV, while with visible source,...
Kinetic and mechanistic study of p-nitrochlorobenzene photoreduction and Bacillus inactivation over aluminosilicate-based nanocomposites
, Article Monatshefte für Chemie - Chemical Monthly ; Volume 144, Issue 5 , May , 2013 , pp 589-596 ; ISSN: 1434-4475 ; Salari, H. (Hadi) ; Sadeghzadeh Darabi, F. (Faramarz) ; Gholami, M. R. (Mohammad Reza) ; Sharif University of Technology
2013
Abstract
Photocatalytic reduction of p-nitrochlorobenzene was studied over aluminosilicate-based AgBr and AgBr-TiO2 photocatalysts which were prepared and characterized. The photoreaction was performed in the presence of LiBH4, which is a strong reducing agent, in the solution medium. A new mechanism is proposed for reduction of p-nitrochlorobenzene under photocatalytic conditions. The effect of pH, illumination source, LiBH4 concentration, temperature, catalyst dosage, and alcoholic scavengers was also studied. The results showed that the best efficiency was obtained over Ag/AgBr/TiO2/aluminosilicates at natural pH under UV light. We observed that the reaction yield was affected by changing the...
Fabrication and antibacterial performance of Ag-Au nanoparticles decorated ionic liquid modified magnetic core-analcime shell microspheres
, Article Journal of Environmental Chemical Engineering ; Vol. 2, issue. 4 , 2014 , p. e1989-e1995 ; Vossoughi, M ; Sharif University of Technology
2014
Abstract
After silica coating of the prepared nickel ferrite nanoparticles, a micrometric layer of zeolitic material (analcime) was grown on the surface. To make the composites good host, surface modification was done with [BMIM]PF6 ionic liquid. Finally, the samples became antibacterial agents via loading the Ag and Au nanoparticles and denoted as X@IL/A/S/NF (X = Ag or Au). All the samples were well characterized by Fourier transform infrared spectroscopy (FTIR), vibrating sample magnetometer (VSM), X-ray diffraction (XRD), scanning electron microscopy (SEM), energy dispersive X-ray (EDX), and N2 adsorption-desorption isotherms (BET) analysis methods. Antibacterial activity of the prepared samples...
Colloidal gold nanoparticles: an unexpected catalytic activity in aqueous phase with dioxygen
, Article catalysis letters ; Volume 144, Issue 7 , July , 2014 , pp. 1219-1222 ; 1572-879X ; Robatjazi, H. (Hossein) ; Hormozi-Nezhad, M. (Mohammad Reza) ; Padervand, M. (Mohsen) ; Gholami, M. R. (Mohammad Reza) ; Sharif University of Technology
2014
Abstract
Selective oxidations of alkenes were investigated using molecular oxygen in aqueous solution under mild conditions. Colloidal gold nanoparticles are particularly versatile catalysts for oxidation reaction with exceptionally high efficiency and significant selectivity. Gold nanorods (Au NRs) exhibited a slightly enhanced activity compare to gold nanospheres
Molecular-microscopic properties and preferential solvation in protic ionic liquid mixtures
, Article Journal of Solution Chemistry ; Volume 42, Issue 9 , October , 2013 , pp. 1757-1769 ; 1572-8927 ; Ahmadvand, S. (Seyedsaeid) ; Harifi-Mood, A. R. (Ali Reza) ; Padervand, M. (Mohsen) ; Gholami, M. R. (Mohammad Reza) ; Sharif University of Technology
2013
Abstract
Structural and molecular-microscopic properties of the solvatochromic probes 4-nitroaniline, 4-nitroanisole, and Reichardt’s dye were investigated in binary mixtures of ethylammonium propionate with methanol, ethanol, 1-propanol and 2-propanol. Solvatochromic parameters (α, hydrogen-bond donor acidity; β, hydrogen-bond acceptor basicity; π*, dipolarity/polarizability; ENT , normalized polarity parameter) in different binary mixtures of ionic liquid with molecular solvents were determined with UV–Vis spectroscopy. The ENT parameters show nearly ideal trends in all solvent mixtures, but the other parameters show different behavior in the mixtures. The π* parameters show a negative deviation...
Removal of toxic heavy metal ions from waste water by functionalized magnetic core-zeolitic shell nanocomposites as adsorbents
, Article Environmental Science and Pollution Research ; Volume 20, Issue 6 , 2013 , Pages 3900-3909 ; 09441344 (ISSN) ; Gholami, M. R ; Sharif University of Technology
2013
Abstract
Functionalized magnetic core-zeolitic shell nanocomposites were prepared via hydrothermal and precipitation methods. The products were characterized by vibrating sample magnetometer, X-ray powder diffraction, Fourier transform infrared spectroscopy, nitrogen adsorption-desorption isotherms, and transmission electron microscopy analysis. The growth of mordenite nanocrystals on the outer surface of silica-coated magnetic nanoparticles at the presence of organic templates was well approved. The removal performance and the selectivity of mixed metal ions (Pb2+ and Cd2+) in aqueous solution were investigated via the sorption process. The batch method was employed to study the sorption kinetic,...
Synthesis of Zeolite-Based NanoComposites and Investigation of their Catalytic Activities
, M.Sc. Thesis Sharif University of Technology ; Gholami, Mohammad Reza (Supervisor)
Abstract
Polyagent photocatalysts based on the zeolite including TiO2, Ag and AgBr prepared by Sol-gel method. Ag and AgBr prevent of electron-hole recombination and enhance photocatalytic activity. Prepared catalysts were characterized by different analysis method including XRD, SEM, EDX, FTIR and BET techniques. Catalyst activities were investigated from two aspects: in first step the activities of catalyst were investigated for degradation of AB92 dye. The effect of different factors such as: catalyst concentration, dye concentration, pH and scavenger (sodium thiosulphate) on efficiency and reaction rate were investigated. The optimazed values for all conditions specified, then catalyst activities...
A novel efficient magnetic core-zeolitic shell nanocatalyst system: Preparation, characterization and activity
, Article Chemical Papers ; Volume 69, Issue 6 , 2015 , Pages 856-863 ; 03666352 (ISSN) ; Vossoughi, M ; Janfada, B ; Sharif University of Technology
De Gruyter Open Ltd
2015
Abstract
Analcime shell-nickel ferrite core microspheres were decorated with Pd and Pt nanoparticles with the aid of an ionic liquid, 1-butyl-3-methylimidazolium hexafluorophosphate (BMIM-PF6). The samples thus prepared were characterized using X-ray powder diffraction (XRD), scanning electron microscopy (SEM), energy dispersive X-ray (EDX), nitrogen adsorption-desorption isotherms, transmission electron microscopy (TEM) and vibrating sample magnetometer (VSM) methods. The XRD patterns confirmed the growth of a zeolitic layer on the surface of the magnetic cores. The thermogravimetric analysis (TGA) curve clearly indicated the thermal decomposition of the loaded IL, which confirmed the presence of...
A mechanistic study and in-vivo toxicity bioassay on acetamiprid photodegradation over the zeolite supported cerium-based photocatalyst
, Article Journal of Photochemistry and Photobiology A: Chemistry ; Volume 395 , 2020 ; Heidarpour, H ; Bargahi, A ; Sharif University of Technology
Elsevier B.V
2020
Abstract
Photocatalysis is well-known as an effective tool for the removal of pollutants but its eco-friendly aspect has not been well explored in the literature. In this study, we prepared an ultraviolet-active photocatalyst by the growth of cerium oxide/sulfide nanoparticles in the zeolite channels via a facile coprecipitation method. The photocatalyst was comprehensively characterized by different analysis methods and showed good activity toward removal of acetamiprid, ACP, a commonly used insecticide. As the main focus of the current work, an in vivo bioassay was carried out to investigate the acute toxicity of the contaminant solutions before and after photoreaction. Accordingly, acetamiprid and...
Copper, gold, and silver decorated magnetic core–polymeric shell nanostructures for destruction of pathogenic bacteria
, Article Russian Journal of Physical Chemistry A ; Volume 91, Issue 5 , 2017 , Pages 936-945 ; 00360244 (ISSN) ; Kiani Karanji, A ; Elahifard, M. R ; Sharif University of Technology
Maik Nauka-Interperiodica Publishing
2017
Abstract
Fe3O4 magnetic nanoparticles (MNPs) were prepared by co-precipitation method. The nanoparticles were silica coated using TEOS, and then modified by the polymeric layers of polypropylene glycol (PPG) and polyethylene glycol (PEG). Finally, the core-shell samples were decorated with Ag, Au, and Cu nanoparticles. The products were characterized by vibrating sample magnetometry (VSM), TGA, SEM, XRD, and FTIR methods. The antibacterial activity of the prepared samples was evaluated in inactivation of E. coli and S. aureus microorganisms, representing the Gram-negative and Gram-positive species, respectively. The effect of solid dosage, bacteria concentration and type of polymeric modifier on the...
Photocatalytic degradation of 3-methyl-4-nitrophenol over Ag/AgCl-decorated/[MOYI]-coated/ZnO nanostructures: Material characterization, photocatalytic performance, and in-vivo toxicity assessment of the photoproducts
, Article Environmental Technology and Innovation ; 2020 ; Heidarpour, H ; Goshadehzehn, M ; Hajiahmadi, S ; Sharif University of Technology
Elsevier B.V
2020
Abstract
In this work, a facile ionic liquid-mediated method was utilized to fabricate an efficient photocatalyst for environmental remediation. The eco-friendly aspect of the treatment was explored through an in-vivo toxicity bioassay. ZnO particles, prepared by a combined solid state-pyrolysis method, were coated by 1-methyl-3-(oxiran-2ylmethyl)-1H-imidazolium-3-chloride ([MOYI]Cl) ionic liquid. Then, Ag/AgCl species were grown on the surface to make a heterojunction system leading to efficient charge separation and light absorption extension to the visible domain. The products were characterized by XRD, FTIR, SEM, EDX, DRS, BET, and PL analysis. Photocatalytic performance of the nanostructures was...
Photocatalytic degradation of 3-methyl-4-nitrophenol over Ag/AgCl-decorated/[MOYI]-coated/ZnO nanostructures: Material characterization, photocatalytic performance, and in-vivo toxicity assessment of the photoproducts
, Article Environmental Technology and Innovation ; Volume 21 , 2021 ; 23521864 (ISSN) ; Heidarpour, H ; Goshadehzehn, M ; Hajiahmadi, S ; Sharif University of Technology
Elsevier B.V
2021
Abstract
In this work, a facile ionic liquid-mediated method was utilized to fabricate an efficient photocatalyst for environmental remediation. The eco-friendly aspect of the treatment was explored through an in-vivo toxicity bioassay. ZnO particles, prepared by a combined solid state-pyrolysis method, were coated by 1-methyl-3-(oxiran-2ylmethyl)-1H-imidazolium-3-chloride ([MOYI]Cl) ionic liquid. Then, Ag/AgCl species were grown on the surface to make a heterojunction system leading to efficient charge separation and light absorption extension to the visible domain. The products were characterized by XRD, FTIR, SEM, EDX, DRS, BET, and PL analysis. Photocatalytic performance of the nanostructures was...
K4Nb6O17/Fe3N/α-Fe2O3/C3N4 as an enhanced visible light-driven quaternary photocatalyst for acetamiprid photodegradation, CO2 reduction, and cancer cells treatment
, Article Applied Surface Science ; Volume 544 , 2021 ; 01694332 (ISSN) ; Ghasemi, S ; Hajiahmadi, S ; Wang, C ; Sharif University of Technology
Elsevier B.V
2021
Abstract
A new magnetic quaternary photocatalyst, K4Nb6O17/α-Fe2O3/Fe3N/g-C3N4, was synthesized via a simple one-step thermal pyrolysis process. The prepared photocatalyst was well characterized, and its photocatalytic activity was evaluated towards acetamiprid pesticide degradation, CO2 reduction reaction, and U87-MG cell eradication. The coexistence of four different crystalline structures in the prepared photocatalyst could simultaneously facilitate photoelectron transport and suppress charge recombination through their coupled heterogeneous interfaces. Because of the coexistence of various photosensitive compounds, the prepared photocatalyst showed the excellent capability to harvest the visible...
Removal of an organic pollutant from waste water by photocatalytic behavior of AgX/TiO2 loaded on mordenite nanocrystals
, Article Research on Chemical Intermediates ; Volume 38, Issue 8 , 2012 , Pages 1975-1985 ; 09226168 (ISSN) ; Salari, H ; Ahmadvand, S ; Gholami, M. R ; Sharif University of Technology
Springer
2012
Abstract
Mordenite (MOR) nanocrystals were synthesized using the hydrothermal method. Sol-gel and deposition methods were utilized to modify the zeolite surface with TiO2 and then AgBr or AgCl particles. Photocatalysts were characterized by using X-ray diffraction, Brunauer-Emmett-Teller (BET), and scanning electron microscopy techniques. Activity was evaluated by photodegradation of Acid Blue 92 as an azo dye. The effect of silver halide deposition on the photocatalytic behavior of the prepared nanocomposites was studied under both ultraviolet (UV) and visible light, and the results were compared. The results showed that AgCl/TiO2/MOR was more active under UV, while with visible source,...